American sycamore Platanus occidentalis
American sycamore (Platanus occidentalis) is a deciduous perennial tree in the Platanaceae family, native to Eastern North America (river floodplains). It grows 22–35 m (72–115 ft) tall and 18–25 m (59–82 ft) wide, wants full sun and high water, and is hardy to about -32 °C (-26 °F). Space plants about 15 m (49 ft) apart.
Plan American sycamore in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
American sycamore at a glance
| Type | Perennial tree, deciduous |
|---|---|
| Family | Platanaceae |
| Mature height | 22–35 m (72–115 ft) |
| Mature spread | 18–25 m (59–82 ft) |
| Spacing | 15 m (49 ft) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | High; drought tolerance low, waterlogging tolerance high |
| Soil pH | 5.5–8 |
| Cold hardiness | About -32 °C (-26 °F) once established (roughly USDA zone 4) |
| Heat stress | Likely above about 40 °C (104 °F) |
| Flowering | from about April for 2–4 weeks (northern hemisphere; later in cold climates, earlier in warm ones) |
| Wind tolerance | Moderate |
| Pollinator value | None |
| Edible | Not grown as food |
| Native to | Eastern North America (river floodplains) |
| Common in gardens of | 🇺🇸 United States |
Is American sycamore toxic?
- People: not known to be toxic
- Cats: not known to be toxic
- Dogs: not known to be toxic
No toxicity reported in ASPCA or standard poison references.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with American sycamore
No well-documented helpful pairing. Group it with plants that like full sun and high water.
See American sycamore in a botanical garden
It grows in these sample gardens, which you can walk through in 3D:
- UC Botanical Garden, Berkeley (1 plants)
- Brooklyn Botanic Garden (1 plants)
- New York Botanical Garden (1 plants)
Questions about American sycamore
- How far apart should I plant American sycamore?
- About 15 m (49 ft) apart, centre to centre. A mature plant spreads 18–25 m (59–82 ft).
- Does American sycamore need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does American sycamore need?
- High water. Drought tolerance is low and waterlogging tolerance high.
- How cold-hardy is American sycamore?
- It tolerates about -32 °C (-26 °F) once established, roughly USDA zone 4.
- When does American sycamore flower?
- From about April for 2–4 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
- Is American sycamore poisonous to cats and dogs?
- For cats it is not known to be toxic; for dogs not known to be toxic; for people not known to be toxic. No toxicity reported in ASPCA or standard poison references.
- What grows well with American sycamore?
- There is no well-documented companion pairing for American sycamore. Group it with plants that like the same sun (full sun) and water (high).
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- Missouri Botanical Garden Plant Finder, Missouri Botanical Garden
- USDA PLANTS Database, USDA NRCS
Notes and assumptions
- Mottled bark peels to show white limbs, the ghosts of riverbanks; among the most massive eastern trees.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- London plane Platanus x hispanica
- Oriental plane Platanus orientalis
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- Black walnut Juglans nigra
- English yew Taxus baccata
- Serviceberry Amelanchier canadensis
- Japanese flowering cherry Prunus serrulata